Method of applying coating to a medical preparation



v Patented Aug. 20, 1935 I UNITEDSTATES PATENT iol-"F gl v 3 Grover 0. Miller Kelp-i Iabo Alhambra, ratories, Inc.,

a'corporatlon oi Calilornia melting point.

at the point 01' the As such a medical compound coat tively high melting surface of the medical which may be very sensitive heat, has proven dimcult.

It is therefore an object of this provide a new and improved metho such a Application July No. 678,926

3, 1933, Serial I 5 Claims. (01. 167-82) which coating material is of a relapplication, Serial No. 648,-

system desired.

ing is of relapoint, its application to the preparations, some of to the application of invention to d of applying coatingto a medical compound or prepapreparation the medicalpreparation being eoa 'Itis method of 'applyingflcoating compoundsand' preparations in: material :tqa ied s here to the surfacesof the or preparation," and. is then encase where points of the human system or an obiectfofflfl is invention or enclose will be apparent rrom the application is desired the stomach and digmtive tracts,

been encountered due to such medicines when In order to overcome this difficulty,

ferred the fact in my co-pending applicati toa coating for a medical for the purpose to encase the has substancompound or to provide a materials to medical medical compound fused together to the medical compound or and advantages of this invention the following of a preferred embodiment particularly at particular points other than difliculty has that most of there is dison above recompound or ing point and which is so This protective medi-' um is a coating which is of relatively high meltcompounded that when it is applied to the surface of medical preparations or medicines it will physically break at a time which may be determined by the coating prepared. v

Such a. coating consists preferably of a coating formed of waxes and'oils, the melting points of which exceed the temperature of the human body mixed with such a substance, for example, 1 as groundagar, which coating will break from the medical compoundv or preparation to which it is applied mechanically under the influence of. moisture as the moisture isjabsorbed by the agar or other substance having the property of dis- 2o integrating on absorption of moisture. An ex-' ample of such a coating is: Powdered agar or any other substance having a high property of mechanical absorption of moisture is mixed with a mixture of oils or waxes, the melting point of which'is determined by the mixture so that the melting point of the resultant compound will be materially above the temperature of the human system as, for example, between 150 to 165 F., dependent upon the time at which it is desired for the coating to break duringthe passage of the coated medical compound through the digestive or colonic tracts. For example, five parts of stearic acid or other oil having a high melting point of approximately 140 F. is' mixed with one part of white wax having a melting point of, for

example, between 143 and 160 1 One part of carnauba wax is then added to the mixture, the, carnauba wax having a melting point of between 181 to 195 F. To this mixture of oils and waxes is then added one part of powdered elm and one part of powdered agar. The mixture is made by melting the oils and waxes together and adding to the mixture of oils and waxes in a mixing or stirring machine the powdered elm and agar.

The degree of fineness to which the agar and powdered elm or other substance having a high property of absorption of moisture is ground, together with the melting points of the oils and waxes employed, determine the time it will require for the coating when it is applied to the medical compounds or medicines to break when passing through the human system.

In preparing the coating, which will require approximately three to four hours to break under to grind the powdered elm-and ;,adhesive to the'surface of l are removed from theabove conditions, 1 have found itad'visable agar to approximesh. As the amount of agar or mately 80 to 90,

having a .high'prcp'erty of abother substance powdered coating material is then added to the stirring machine and the stirring continued until the powdered materialhas adhered tc'the s'urface of the medical compoundor preparation... In coating small pills of medical preparations. I have .found that approximately 2 ounces of powdered coating material may beutilized for very effectively coating 1 pound of tablets or pills. The powdered coating material is held'by the the particles of the coating material are, by the mixing, caused to adhere together.

After the application of the powdered coating" material to the surface of the tablets orpills, they the mixing machine and placed the tablet'or pill and j surface of the stearic acid. The stearic the exterior of thepowdered coatin material and under the influence of the flame as applied to the pills or tablets, a small quantity .0: 5 acid thus is applied to about 140 F. to a'medical preparation for 7 sion in the intestinaltract which includes the, v

steps of reducing-the coating material to a state of relatively line.

an adhesive, and then of .a flame the coating to. the preparation.

4. A method of applying an enteric coating of an oil or wax of a melting point of not lower than sorption to moisture is increased in the coating surface of the pills, is not'burned away but gives 3 as above set forth, the time required forthe splitto the resultant coating preparations a relatively tingofthecoatingdecreased. 1 8 81058- 311 The coating as thus prepared: which is given Having fully described mydnvention, it is to be merely as an illustrative example, and my invenunderstood that I do not wish to be limited to tion'is not in any way dependent upon the specific details herein set forth, butmy invention is of the 10 illustrative example given. of such a coatingiI 111 5 1 1 the pp c a permit the coating to cool and then reducethe Iclaim; coating material to a-state of relatively flne 1. A method of applying enteric coating of division by any suitable or desirable means such, an oil or wax of a melting point of not lower than i J for example, as by grating the materialthrough 140 F. to a medical preparation foradmission in 15- av mechanical grater, and I preferably-reduce ',the intestinal tract including the steps of reducthe coating material as above set forth to a rela- 'ing the coating to a relatively fine owd r, gpply- J tively fine state of subdivision so'that it will pass ing an adhesive substance ,to the preparation, 7 through an mesh screenj t then covering the preparation with the powdered The medical preparation or m cine to be coating and fusing by direct application of a. a0 coated, preferably in a solid, or semi-solid state, flame-the coating on the preparation. l is then placed in a mix ing machine to which a A m h d of a ply 1$ m 0! small quantity of an adhesive material is added. an oil or was of-a melting point of not lower than ,The adhesive material may be such a substance about F- to medical p parat on for admisas white shellac dissolved in alcohol or may be sion in the intestinal tract including t e steps of 25 such a substance "benzoine dissolved in 9100- applyinga coating t9 th pm p p hol, or any other isimilar adhesive substances. and h 11151118 y direct app a l 0f 8 fl The medical preparation and the adhesive are the W t0 0 e Preparationfthen stirred together so, as to thoroughly coatfimethod applying an enteric coatin 01*" the medical preparation with the adhesive. "The an 011 or w r a m n p n of not e h st subdivision, applying the iinely I V divided coatingmaterial to the preparation with; 5'

fusing by direct application "then fusing thecoating to the preparation by applying to the surface ofthe preparation- .on trays and'are then subjected to a relatively 7 high temperature for'a relatively short period of time in order to. fuse the particles of the coatingv Y materials together. The application of heat tothecoating material may be effectively performed by passing the tray of pills or tablets with the coating material on its surface under a high ten, 'perature flame. In order that all surfaces may be as coated with the finely divided coating a relatively high temperature flame for a short intervaloftime. 5.--A method of applying an enteric co'ating'of an oil'or wax of a. melting pointof not-lower about 140 F. to a medical preparation for'admis" son in the intestinal-tract including the steps of the tablets or, pills are coating is fused on all sides.

exposedto the action of'high temperature flame,

turned over so that the Obviously other means may be employed for imparting to the coating material a high temperature in order to effect the desired fusing. when it isdesired to give pills or tablets a glossy finish, I prefer to add to the mixing machine after the powdered coating material is to the r jm h coating tively. flne subdivision,

tion;

coating material to the preparation, and-then fusing the coatingto the preparation by applying" relativeLv-intense heat of a direct flame for a relatively short interval'of time to the finely dividedcoating material on the Gaovua c. mum.

material to a state of rela-' applying the finely divided surfaces of the prepara 

